12387728 has 10 divisors (see below), whose sum is σ = 24001254. Its totient is φ = 6193856.

The previous prime is 12387709. The next prime is 12387733. The reversal of 12387728 is 82778321.

It can be written as a sum of positive squares in only one way, i.e., 8111104 + 4276624 = 2848^2 + 2068^2 .

It is a junction number, because it is equal to n+sod(n) for n = 12387691 and 12387700.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 387101 + ... + 387132.

Almost surely, 2^12387728 is an apocalyptic number.

It is an amenable number.

12387728 is a deficient number, since it is larger than the sum of its proper divisors (11613526).

12387728 is an equidigital number, since it uses as much as digits as its factorization.

12387728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 774241 (or 774235 counting only the distinct ones).

The product of its digits is 37632, while the sum is 38.

The square root of 12387728 is about 3519.6204340809. The cubic root of 12387728 is about 231.3825236985.

The spelling of 12387728 in words is "twelve million, three hundred eighty-seven thousand, seven hundred twenty-eight".